It's a gamble but it doesn't sound too bad a price if it is in fact a GM backed warranty. I don't trust aftermarket warranties, I've bought only a few over the years and each time I had a claim they did their best to get out of it. My last warranty was for my Audi and I only bought it because I didn't know how to work on that one (been a GM many my whole life). When I had an oil leak it took 3 days of playing mediator between the warranty company and the dealership because they tried to deny my entire claim, claiming the oil gasket that needed replacing wasn't an oil gasket even though it is officially labeled as an oil seal. My $100 deductible ended up costing me about $450 in repairs because of one other oil gasket which they wouldn't pay for even though the repair involved replacing that gasket because of another part that had to be removed to perform the needed oil leak repair.
I look at it this way, I won't buy an extended warranty anymore. Mostly because I can do my own work, have several vehicles so I can have one down for awhile if needed, and salvage yard parts are cheap. If you can't afford to pay for a new engine or transmission then an extended warranty is good for peace of mind as long as the company backing it will actually pay for repairs.
